NORTHERN POLYPORES 17 



coriaceous above, fibrous-woody below, white, 0.5-1.5 cm. thick; 

 tubes 4-8 mm. long, white to pallid within, mouths angular, 

 irregular, somewhat radiately elongate, sinuous at times, 1-2 

 to a mm., stuffed when young, edges thin, white to ochraceous, 

 dentate to lacerate; spores ovoid, 5-6 X 3-4 /*. 



Occasional throughout on various coniferous trunks, and 

 more frequent northward, causing serious decay. 



4. SPONGIPELLIS DELECTANS (Peck) Murrill 



Pileus simple or subimbricate, dimidiate, convex or subtri- 

 angular, fleshy-fibrous to corky, 5 X 5-10 X 2-5 cm.; surface 

 azonate, white to ochraceous-isabelline, uneven, glabrous or 

 slightly floccose-tomentose ; margin thin, acute, concolorous, 

 sterile; context soft and spongy above, firm and woody below, 

 white, I cm. or more thick; tubes 5-8 mm. long, white within, 

 mouths large, subcircular or angular, somewhat irregular, 1-3 

 to a mm., edges thin, entire to slightly dentate, white to slightly 

 discolored; spores subglobose to ovoid, 7-8 X 5-6 (j.. 



Frequent on diseased trunks of maple, elm, and certain other 

 deciduous trees in Ohio and Indiana. 



5. SPONGIPELLIS GALACTINUS (Berk.) Pat. 



Pileus cespitose-imbricate, soft, spongy and watery when 

 fresh, rigid and brittle when dry, dimidiate or reniform, elongate 

 behind, applanate or convex, much contorted on drying, 3-5 

 X 5-10 X 0.5-1 cm.; surface hispid or strigose-tomentose, 

 white, azonate, smooth or slightly tuberculose, becoming isa- 

 belline on drying; margin thin, but often obtuse, sterile, entire, 

 discolored and inflexed when dry; context zonate, firm, fibrous- 

 woody below, spongy above, 3-7 mm. thick; tubes 3-5 mm. 

 long, slender, white to isabelline, mouths minute, white, glisten- 

 ing, angular or slightly flexuose, 6 to a mm., edges very thin, 

 lacerate-dentate, at length isabelline; spores ellipsoid, 3-4 

 X 1.5-2/1. 



Frequent on dead or diseased trunks of deciduous trees from 

 eastern Canada to Ohio. 



7. BJERKANDERA P. Karst. 



Hymenophore annual, epixylous, sessile, anoderm, glabrous, 

 azonate, corky; context white, tough or woody, not friable when 

 dry; tubes thin-walled, more or less smoke-colored, mouths 

 polygonal; spores smooth, hyaline. 



